On some Android devices (e.g. Android S1RXS32.50-13-25) the WorkManager platform channel fails to connect at startup, throwing PlatformException(channel-error, ...). registerBackgroundSync() now catches PlatformException and MissingPluginException (plus any other unexpected failure) and silently disables background sync rather than crashing the app. Test added: test/unit/background_sync_test.dart verifies the function completes without throwing in the unit-test environment (where the native plugin is absent). Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>